The present invention relates generally to a portable system for transporting fluids from a source of purified water or dialysate to individual dialysis machines in a dialysis clinic.
It will be appreciated by those skilled in the art that present systems used for fluid delivery to dialysis machines in dialysis clinic pose problems due to limited space and incidence of bacterial contamination. Furthermore, these systems are installed as permanent fixtures, making them expensive to install, expensive to disinfect, expensive to repair, and expensive to replace. Presently used systems installed as permanent fixtures physically depreciate over time, without the tax advantage of financial depreciation allowed for non-permanent equipment.
The prior art systems provide fluids from a fixed water treatment plant in one part of a building to the dialysis machines in another room. This distance requires that long "runs" be used to transport fluids from the water treatment facility to the dialysis machines. This means that the prior art systems use large runs of piping.
It will be further appreciated by those skilled in the art that bacterial contamination is a common problem in presently available systems. Standard plumbing design and polyvinyl chloride pipes are commonly used. The use of PVC piping and solvent welding methods of joining and fabrication of existing fluid delivery systems results in the creation of cavities which cannot adequately be disinfected by conventional clean in place procedures used by dialysis clinics.
It will be further appreciated that there is a broad range of PVC mixtures utilizing a variety of stabilizers and plasticizers which over time leach into the fluid stream, and that the interior pipe surface becomes pitted and more conducive to trapping bacteria and supporting bacterial growth.
It will be further appreciated by those skilled in the art that present systems require a significant amount of space, restricting mobility within a dialysis clinic and making the use of more heat-resistant yet expensive tubing, such as polytetrafluoroethylene (Teflon.RTM.) tubing cost prohibitive. Instead the predominant current practice for dialysate distribution piping makes use of chemical clean in place disinfection in materials (e.g. PVC) which are incompatible with heat disinfection. Furthermore, present systems are piped in permanent structures; chaises or bulky consoles that do not permit easy access, repair or replacement.
It will be further appreciated by those skilled in the art that heat disinfection means are preferable to chemical disinfection means in these systems. Chemical disinfectants presently in use include strong oxidizing agents. Residual disinfectant not adequately flushed from the system poses a hazard to patients. For example, a common chemical disinfectant, formaldehyde, has been shown to cause some repeat dialysis patients to develop antibodies to the N-antigens on the surface of their own red blood cells. The present invention facilitates the use of heat disinfection by providing materials of construction that can be operated at high temperature.
It will be further appreciated by those skilled in the art that, despite the use of chemical disinfectants, present systems still experience problems with bacterial contamination. Regular assay for endotoxin in the system is required. Furthermore, multiple connection points and ready access to those connections makes current systems more susceptible to deliberate tampering by unauthorized personnel.
What is needed then is a system which facilitates heat disinfection and eliminates solvent welded joints. This needed system must eliminate "dead legs" in the system. A "dead leg" is generally defined as a dead end length of pipe of greater than five pipe diameters in length. This needed system must decrease equipment surface area in the dialysis clinic, facilitating disinfection. This needed system must provide replaceable components which are easily installed, repaired, and replaced, yet protected from potential tampering by unauthorized individuals. This needed system must be capable of use without being attached to real property. This needed system must use quick disconnects to permit easy placement of components. This needed system is presently lacking in the prior art.